Self check mechanism in Spring Cloud Alibaba Dubbo

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**Which Component**
eg. spring-cloud-starter-alibaba

**Describe what problem you have encountered**
Sometimes there were much Exception like this:
```
org.apache.dubbo.rpc.RpcException: No provider available in [invoker :interface org.apache.dubbo.rpc.service.GenericService -> spring-cloud://localhost:9090/org.apache.dubbo.registry.RegistryS
ervice?anyhost=true&application=xxx-service&bind.ip=10.0.68.162&bind.port=20887&check=false&deprecated=false&dubbo=2.0.2&dynamic=true&generic=true&group=xxx1-service&interf
ace=com.alibaba.cloud.dubbo.service.DubboMetadataService&lazy=false&methods=getAllServiceKeys,getServiceRestMetadata,getExportedURLs,getAllExportedURLs&pid=3595&qos.enable=false®ister=true&
register.ip=10.0.68.162&release=2.7.3&remote.application=xxx1-service&revision=2.1.0.RELEASE&side=consumer&sticky=false&timeout=50000×tamp=1615491177605&version=1.0.0,directo
ry: org.apache.dubbo.registry.integration.RegistryDirectory@5ede64ae, invoker :interface org.apache.dubbo.rpc.service.GenericService -> zookeeper://a.b.c.d:2181/org.apache.dubbo.regi
stry.RegistryService?anyhost=true&application=xxx-service&check=false&deprecated=false&dubbo=2.0.2&dynamic=true&generic=true&group=xxx1-service&interface=com.alibaba.cloud.
dubbo.service.DubboMetadataService&lazy=false&methods=getAllServiceKeys,getServiceRestMetadata,getExportedURLs,getAllExportedURLs&pid=3595&qos.enable=false®ister=true®ister.ip=10.0.68.16
2&release=2.7.3&remote.application=xxx1-service&revision=2.1.0.RELEASE&side=consumer&sticky=false&timeout=50000×tamp=1615491177605&version=1.0.0,directory: org.apache.dubbo.r
egistry.integration.RegistryDirectory@48837d47]
at org.apache.dubbo.rpc.cluster.support.RegistryAwareClusterInvoker.doInvoke(RegistryAwareClusterInvoker.java:59)
at org.apache.dubbo.rpc.cluster.support.AbstractClusterInvoker.invoke(AbstractClusterInvoker.java:248)
at org.apache.dubbo.rpc.cluster.support.wrapper.MockClusterInvoker.invoke(MockClusterInvoker.java:78)
at org.apache.dubbo.rpc.proxy.InvokerInvocationHandler.invoke(InvokerInvocationHandler.java:55)
at org.apache.dubbo.common.bytecode.proxy96.$invoke(proxy96.java)
at com.alibaba.cloud.dubbo.service.DubboMetadataServiceInvocationHandler.invoke(DubboMetadataServiceInvocationHandler.java:49)
at com.sun.proxy.$Proxy563.getExportedURLs(Unknown Source)
at com.alibaba.cloud.dubbo.registry.AbstractSpringCloudRegistry.getExportedURLs(AbstractSpringCloudRegistry.java:328)
at com.alibaba.cloud.dubbo.registry.AbstractSpringCloudRegistry.subscribeDubboServiceURL(AbstractSpringCloudRegistry.java:260)
at com.alibaba.cloud.dubbo.registry.AbstractSpringCloudRegistry$1.onApplicationEvent(AbstractSpringCloudRegistry.java:193)
at com.alibaba.cloud.dubbo.registry.AbstractSpringCloudRegistry$1.onApplicationEvent(AbstractSpringCloudRegistry.java:186)
at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172)
at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(Simpl
```
A clear and concise description of what you want to do.

**Describe what information you have read**
I try to solve this problem wrote before. so I read source code of spring-cloud-dubbo-starter, and this article: [Apache-Dubbo-服务自省架构设计](https://mercyblitz.github.io/2020/05/11/Apache-Dubbo-%E6%9C%8D%E5%8A%A1%E8%87%AA%E7%9C%81%E6%9E%B6%E6%9E%84%E8%AE%BE%E8%AE%A1/), wrote by @mercyblitz .

the mechanism:
1. `spring-cloud-zookeeper-discovery` will add service info in this node `/services` .
2. When using `spring-cloud-starter-dubbo`, there will be two register conter in dubbo, one is you use such as Zookeeper, another is SpringCloud, that from `com.alibaba.cloud.dubbo.registry.SpringCloudRegistry`. All of the providers and consumers will listen a different `ApplicationListener`. This logic is written in `com.alibaba.cloud.dubbo.registry.AbstractSpringCloudRegistry#registerServiceInstancesChangedEventListener`.
3. When `ServiceInstancesChangedEvent` were published, all listeners will call relative DubboMetadataService. It will has much call when just start.If more than one service are restarting, that will throw much Exception like mentioned above.

I have some opinions:
1. Whether it need a warn time when startup before sefl checking ?
2. There is a configuration which can close listen zookeeper's childevent, `spring.cloud.discovery.enabled`, however, this is a spring cloud configuration, if I close it, my gateway won't find that service.
3. If one interface check failed, whether other interface from that service don't need check? Or provide a backoff strategy.
4. When adding a listener, I think it can just add consumer interface listener, because the provider is itself.

Start with com.alibaba.cloud.dubbo.registry.AbstractSpringCloudRegistry#registerServiceInstancesChangedEventListener and trace the getExportedURLs and subscribeDubboServiceURL calls mentioned in the stack trace. Read the linked Apache Dubbo service introspection article and compare the startup listener behavior with the reported failures. Done requires an agreed self-check mechanism and its behavior for startup timing, failed interfaces, and listener scope.

Written by the indexing model from the issue text.